Significant Structures of the Knee Joint

Question 1

What are the two joints that make up the knee?

Answer 1

tibiofemoral, patellofemoral

Question 2

What type of joint is the knee joint?

Answer 2

Hinge

Question 3

Why is the knee hinge joint more complex than the elbow hinge joint?

Answer 3

rounded condyles roll across the superior surface of the tibia (points of contact are constantly changing), some degree of rotation is permitted

Question 4

patellar ligament

Answer 4

patella embedded within the patellar ligament, anterior surface of joint, provides support to anterior surface of knee where there is no continuous capsule

Question 5

tibial collateral ligament (MCL) attachment

Answer 5

medial reinforcement, from the lateral epicondyle of the femur to the head of the fibula

Question 6

fibular collateral (LCL) attachment

Answer 6

lateral reinforcement, from the medial epicondyle of the femur to the medial surface of the medial condyle of the tibia

Question 7

What do the MCL and LCL have in common during full extension?

Answer 7

tighten only at full extension where they stabilize the joint

Question 8

arcuate popliteal ligament

Answer 8

posterior aspect of the head of fibula, restrains excessive tibial rotation, fibers pass superiomedially over tendon of popliteus then blend with articular capsule of knee

Question 9

oblique popliteal ligament

Answer 9

extends across the back of knee from medial condyle of the tibia to the lateral condyle of the femur, blends with central, posterior part of the fibrous later of the articular capsule of the knee

Question 10

anterior cruciate ligament (ACL) attachment

Answer 10

from anterior aspect of the intercondylar eminence of the tibia with the medial surface of the lateral femoral condyle

Question 11

posterior cruciate ligament attachment

Answer 11

from the posterior aspect of the intercondylar eminence of the tibia to the lateral surface of the medial femoral condyle

Question 12

ACL Function

Answer 12

limits anterior movement of the tibia relative to the emir in all positions of joint movement

Question 13

PCL Function

Answer 13

limits posterior movement of the tibia relative to the femur in all positions of joint movement

Question 14

What happens to the MCL in a clipping type injury (knee abduction)

Answer 14

ligament tears with meniscus because of its attachment to the medial meniscus

Question 15

posterior meniscofemoral ligament attachment

Answer 15

from the posterior part of the lateral meniscus to the lateral surface of the medial femoral condyle

Question 16

Function of posterior meniscofemoral ligament

Answer 16

supports PCL in reducing posterior displacement of tibia on femur - controls the motion of the lateral meniscus in conjunction with the tendon of popliteus muscle during flexion

Question 17

What nerve does the patella tendon reflex test for?

Answer 17

L4

Question 18

Why injury is the medial meniscus (semilunar cartilage) more susceptible too? Why?

Answer 18

because of its attachment to the MCL, it is more likely injured from displacement or twisting injuries

Question 19

What are the two intercondylar attachements between the tibia and femur?

Answer 19

the cruciate ligaments (ACL/PCL)

Question 20

What are the two main voluntary motions of the knee?

Answer 20

flexion and extension

Question 21

What are the minor motions of the knee?

Answer 21

anterior/posterior, medial/lateral glides, anteriomedial/posteriomedial

Question 22

Postero-lateral glide dysfunction

Answer 22

extension of the knee, lateral condyle reaches physiologic limit and articular surface of medial condyle of femur continues to track on tibial plateau causing internal rotation of tibia - posterior and lateral glide of the tibial plateau in full extension

Question 23

antero-lateral glide dysfunction

Answer 23

happens in full flexion, lateral condyle of femur finds barrier sooner therefore the medial condyle continues to roll over tibial plateau which causes tibia to rotate externally - glide tibial plateau anteriorly and medially

Question 24

Gastrocnemius Origin

Answer 24

Femur; medial head: above the medial femoral condyle
Lateral head: above the lateral femoral condyle

Question 25

Gastrocnemius Insertion

Answer 25

dorsum of the calcaneus (achilles tendon)

Question 26

Gastrocnemius Action

Answer 26

Flexes leg; plantar flexes the foot

Question 27

Popliteus Origin

Answer 27

lateral condyle of the femur

Question 28

Popliteus Insertion

Answer 28

posterior surface of the tibia above soleal line

Question 29

Popliteus Action

Answer 29

flexes and rotates leg medially (with foot planted, it rotates the thigh laterally)

Question 30

Plantaris Origin

Answer 30

above the lateral femoral condyle (above the lateral head of gastrocnemius)

Question 31

Plantaris Insertion

Answer 31

dorsum of the calcaneus medial to the calcaneal tendon

Question 32

Plantaris Action

Answer 32

flexes leg, plantar flexes the foot

Question 33

Semimembranosus Origin

Answer 33

upper, outer surface of the ischial tuberosity

Question 34

Semimembranosus Insertion

Answer 34

Medial Condyle of tibia

Question 35

Semimembranosus Action

Answer 35

extends thigh, flexes leg